• 생명과학회지
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• 제14권1호
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• pp.193-197
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• 2004

A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing large patch disease of turfgrass. Six isolates consistently suppressed large patch in turfgrass, and ranged in the spectrum of extracellular enzymes that they expressed. The best disease- suppressing isolate, TBM912, expressed protease, CMCase, and pectinase activity and inhibited the growth of Rhizectonin solani and Betrytis cinerea in vitro. Here we show that this strain also produces an antibiotic that was identified by TLC, SDS-PACE and HPLC analysis as lipopeptide.

• The Plant Pathology Journal
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• 제18권2호
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• pp.102-105
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• 2002

A strain of Acremonium strictum, the mycoparasite of Botrytis cinerea, showed strong antifungal activities both in vitro and in vivo against several phytopathogenic fungi. An antifungal substance was purified from the liquid cultures of A. strictum and identified as verlamelin by instrumental analyses. Verlamelin exhibited in vitro antifungal activity against some phytopathogenic fungi such as Magnaporthe grisea, Bipolaris maydis, and Botrytis cinerea, while it was net active against all the bacteria tested. In viva, verlamelin exhibited strong protective and curative activities, particularly against barley powdery mildew. At 100 μg/ml, it inhibited the development of barley powdery mildew with control values of more than 90% in 7-day protective and 2-day curative applications. This is the first report on the production of verlamelin by Acremonium species.

• Journal of Microbiology and Biotechnology
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• 제20권10호
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• pp.1397-1402
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• 2010

Papyriflavonol A (PapA), a prenylated flavonoid [5,7,3',4'-tetrahydroxy-6,5'-di-(${\gamma},{\gamma}$-dimethylallyl)-flavonol], was isolated from the root barks of Broussonetia papyrifera. Our previous study showed that PapA has a broad-spectrum antimicrobial activity against pathogenic bacteria and fungi. In this study, the mode of action of PapA against Candida albicans was investigated to evaluate PapA as an antifungal agent. The minimal inhibitory concentration (MIC) values were 10~25 ${\mu}g/ml$ for C. albicans and Saccharomyces cerevisiae, Gram-negative bacteria (Escherichia coli and Salmonella typhimurium), and Gram-positive bacteria (Staphylococcus epidermidis and Staphylococcus aureus). The kinetics of cell growth inhibition, scanning electron microscopy, and measurement of plasma membrane florescence anisotrophy revealed that the antifungal activity of PapA against C. albicans and S. cerevisiae is mediated by its ability to disrupt the cell membrane integrity. Compared with amphotericin B, a cell-membrane-disrupting polyene antibiotic, the hemolytic toxicity of PapA was negligible. At 10~25 ${\mu}g/ml$ of MIC levels for the tested strains, the hemolysis ratio of human erythrocytes was less than 5%. Our results suggest that PapA could be a therapeutic fungicidal agent having potential as a broad spectrum antimicrobial agent.

• 한국균학회지
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• 제30권2호
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• pp.147-151
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• 2002

Trichoderma속 균주는 느타리버섯 재배 시 발생되는 버섯 푸른곰팡이병의 주요 원인균이다. 후발효된 버섯 배지로부터 버섯 푸른곰팡이병균에 항균활성을 나타내는 길항세균(KATB 99121, KATB 99122 및 KATB 99123)을 분리하였다. 분리세균 중 KATB 99121은 T. harzianum(4균주). T. viride 및 T. hamatum과 동물병원성 곰팡이 Candida albicans에 대하여 우수한 억제 활성이 관찰되었고, 특히 세균의 배양상등액 접종실험에서 강한 항균활성을 보였다. 또한, KATB 99121은 전분, 단백질 및 섬유소를 분해하는 효소를 세포외로 분비하는 것으로 관찰되었고, KATB 99122와 KATB 99123은 전분, 단백질, 섬유소 분해효소는 물론 지질 분해효소도 분비하고 있었으며 ${\beta}$-glucosidase활성도 높은 것으로 확인되었다. 앞으로 이들 길항세균들을 이용하여 느타리버섯 푸른곰팡이병 방제를 위한 미생물 살균제의 개발에 대한 연구를 수행할 예정이다.

• 치위생과학회지
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• 제18권1호
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• pp.18-23
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• 2018

Propolis has been used as a natural remedy in folk medicine worldwide. The antibacterial, antiviral, antifungal, and antiprotozoal aspects of its antimicrobial properties have been widely investigated. However, few studies focused on its applications in dentistry. Many dental diseases are related to various microorganisms in the oral cavity. In this study, we assessed the antimicrobial activity of Korean propolis extract, collected from 6 different regions, on oral pathogenic microorganisms. The propolis samples, collected from 6 different regions (P1: Uijeongbu, P2: Ansan, P3: Hongcheon, P4: Iksan, P5: Gwangju, and P6: Sangju), were dissolved in ethanol at two different concentrations (10 and 50 mg/ml). Three oral bacteria (Streptococcus mutans, Staphylococcus aureus, and Enterococcus faecalis) and one fungus (Candida albicans) were activated in general broth for 24 hours. Microorganisms were diluted and spread onto agar plates, onto which sterilized 6 mm filter papers with or without each propolis sample were placed. After 24 hours of incubation, clear zones of inhibition were observed. All tests were performed in triplicate. The propolis samples showed significant antibacterial and antifungal activity on oral pathogenic microorganisms; in addition, low-concentration groups showed outstanding antimicrobial efficacy on the 4 different microorganisms. Among the samples, P6 had significantly higher antibacterial activity than that of the others against three different bacteria. In particular, a high concentration of P6 showed a significant antifungal effect. In conclusion, we confirmed that Korean propolis has an inhibitory effect on oral pathogenic bacteria and fungi. Therefore, we suggest the possibility of developing oral medicine and oral care products based on Korean propolis.

• 한국균학회지
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• 제42권4호
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• pp.333-340
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• 2014

미생물을 이용한 생물학적 방제제의 개발을 위해 연작피해가 없는 순창군 토양으로부터 다양한 미생물 201종을 분리하였고, 이들의 생물학적 활성을 조사하였다. 201종의 분리 세균 중에서 다양한 식물병원성 곰팡이에 대하여 항균활성이 우수한 5종을 선별하였다. 5종의 분리주에 대하여 siderophore를 생산하며 cellulase, protease, amylase와 같은 곰팡이 세포벽 분해효소를 생산하는 능력이 가장 우수한 SCS3 균주를 최종 선별하였다. 최종 선별한 균주 SCS3의 형태학적, 생리학적 및 생화학적 특성을 조사하였고, 16S rRNA 염기서열의 분석에 의해 B. subtilis SCS3으로 명명하였으며, 염기서열 분석에 기반하여 계통수를 작성하였다. 이상의 결과로부터 B. subtilis SCS3은 식물병원성 곰팡이의 방제를 위한 생물학적 방제제로 유용하게 이용될 수 있을 것으로 생각한다.

• 한국환경농학회지
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• 제30권3호
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• pp.346-356
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• 2011

BACKGROUND: Chemical fungicides not only may pollute the ecosystem but also can be environmentally hazardous, as the chemicals accumulate in soil. Biological control is a frequently-used environment-friendly alternative to chemical pesticides in phytopathogen management. However, the use of microbial products as fungicides has limitations. This study isolated and characterized a three-antifungal-enzyme (chitinase, cellulase, and ${\beta}$-1,3-glucanase)-producing bacterium, and examined the conditions required to optimize the production of the antifungal enzymes. METHOD AND RESULTS: The antifungal enzymes chitinase, cellulase, and ${\beta}$-1,3-glucanase were produced by bacteria isolated from an sawmill in Korea. Based on the 16S ribosomal DNA sequence analysis, the bacterial strain AM50 was identical to Streptomyces sp. And their antifungal activity was optimized when Streptomyces sp. AM50 was grown aerobically in a medium composed of 0.4% chitin, 0.4% starch, 0.2% ammonium sulfate, 0.11% $Na_2HPO_4$, 0.07% $KH_2PO_4$, 0.0001% $MgSO_4$, and 0.0001% $MnSO_4$ at $30^{\circ}C$. A culture broth of Streptomyces sp. AM50 showed antifungal activity towards the hyphae of plant pathogenic fungi, including hyphae swelling and lysis in P. capsici, factors that may contribute to its suppression of plant pathogenic fungi. CONCLUSION(S): This study demonstrated the multiantifungal enzyme production by Streptomyces sp. AM50 for the biological control of major plant pathogens. Further studies will investigate the synergistic effect, to the growth regulations by biogenic amines and antifungal enzyme gene promoter.

• 식품보건융합연구
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• 제9권6호
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• pp.1-7
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• 2023

Secondary metabolites in the culture filtrates of lactic acid bacteria offer varied chiral moieties, making them a valuable resource for drug design scaffolding. Our previous methodology included using a combination of anion exchange resins, Amberlite IRA-67 and Purolite A420S, to purify significant quantities of Lactobacillus plantarum LBP-K10 peptidyl compounds. However, current experimental evidence regarding the impact of native culture extracts and/or filtrates on pathogenic fungi in vivo/in vitro is insufficient. This study analyzed the antifungal properties of two different probiotic cultures: the CH₂Cl₂-extracted filtrate of Chinese cabbage kimchi (CH₂Cl₂-extracted CCK_WLB and CH₂Cl₂-extracted CCK_WOLB) and the non-extracted filtrate of Chinese cabbage kimchi (non-extracted CCK_WLB and non-extracted CCK_WOLB). The samples were divided into two groups: one group was inoculated with probiotics while the other group remained non-inoculated. Filtrates from both experimental groups were utilized for antifungal assays. The treatments employing CCK_WLB, with an initial inoculation of Lb. plantarum LBP-K10 as a starter, demonstrated significant antifungal activity under various experimental conditions. Our study offers new perspectives on the antifungal properties of CH₂Cl₂-extracted kimchi filtrates, which are naturally produced by lactobacilli. The efficacy of antifungal compounds is supported by substantial evidence demonstrating their efficient uptake by cells and the antifungal properties exerted by metabolites.

• 한국균학회지
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• 18권2호
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• pp.96-101
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• 1990

양송이 주요병해인 마이코곤병(M. perniciosa)의 생물적방제를 위한 항균성 미생물을 선발하기 위하여 실시한 시험 결과를 요약하면 다음과 같다. 1. 미생물의 분리는 Starch casein, Soybean meal, Oat meal 배지에서 균집락 형성과 균집락의 특성이 다른 배지 보다 빠르며, 다양한 미생물의 분리가 용이하였다. 2. 실내시험에서 사상균 91, 세균 342, 방사선균 556균주의 미생물을 분리 선발한 후 Oat meal 배지에서 대치배양하여 항균력이 높은 세균 12, 방사선균 71균주를 선발하였다. 3.실내에서 항균력이 있는 균주에 대해 실시한 1차 포장시험에서 5개 균주가 수량 및 항균력이 우수하였으며, 확인시험에서는 AJ-117, AJ-136, AK-139의3균주가 뚜렷한 항균력이 있었다.

• 한국토양비료학회지
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• 제48권5호
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• pp.485-491
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• 2015

This study was performed to investigate thermophilic bacteria from soil having broad antifungal spectrum against Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f.sp. lycopersici, and Botrytis cinerea. One isolate selected could resist heat shock of $60^{\circ}C$ for one hour, and had broad antifungal activity in dual culture assay against all tested fungal pathogens and was identified as Bacillus amyloliquefaciens Y1 using 16S rRNA gene sequence. Further investigation for antifungal activity of bacterial culture filtrate (BCF) and butanol crude extract (BCE) of various concentrations showed broad spectrum antifungal activity and fungal growth inhibition significantly increased with increasing concentration with highest growth inhibition of 100% against R. solani with 50% BCF and 11 mm of zone of inhibition against R. solani with 4 mg BCE concentration. Treatment of butanol crude extract resulted in deformation, lysis or degradation of C. gloeosporioides and P. capsici hyphae. Furthermore, B. amyloliquefaciens Y1 produced volatile compounds inhibiting growth of R. solani (70%), C. gloeosporioides (65%) and P. capsici (65-70%) when tested in volatile assay. The results from the study suggest that B. amyloliquefaciens Y1 could be a biocontrol candidate to control fungal diseases in crops.